Manufacture of paper-pulp from wood



' UNITED STATES-- PAT NT OFFICE.

WILLIAM E. nnnnnnnyor ,PHILA'IQELPHIA, PENHSYLVANTA.

MANu AeTuRE'oi- PAPER-PULP, FROM WOO D, 84;

1 BiEGIFIGATIQN farming-ppm of Letters Patent No-. 22a,c7o,- dated January 20, 1880,. i I 7 Application filed September 27, 1879. i

To an whom it may concern Be it known that I, WILLIAM E. FARR L of the city and county of Philadelphia, and the State of Pennsylvania, have invented certain new and useful Improvements in theProcess of Manufacturing Paper-Pulp from Wood and other Vegetable Fibrous'Material'; and I do hereby declare the following to be a-full, clear, and'exactdescription of the same.

My invention has -reference to an improvement on the process described in my Letters Patent No. 215,7 28, dated May 27, 187 9, granted to me. on an application filed" April 18,

"1878. The vnature ofmy. invention will be. fully.

shownint'h e'follo'wing speci fieation and claims.

the-weed, whieh wemor dry;

into any-convenient or suitable lengths" or sized pieces by any of themany well-known devices used for that purpose. 7 I Wood cut at right. angleswith the grain will pulp. more rapidly;-but wood out at an acuteangle orparallel with the grain,-while taking a longer time to pulp or reduce to fiber, makes a betterand ionger-fibered pulp. Sawdust, by -my process, will make a fair paper-puip, .better-tthan the ground wood pulp.

Q'My first: step is to-soak the woodto be 0 pulped. Thewood being cut ,as desired, '1

place it in a. suitable. pan or vessel which may 'Q be steam and.water tight, having the neces-.- sary outlet and inlet'valves and screens for I cover the the subsequent manipulation. 5 wood with water, and to hasten the thorough, soaking of the woody fibers, I now introduce steam to-heat the'wood and water to any degree desired. 7

capable of sustaining any pressure required, as some Woods will take up the Water at a low'pressure, some require a highpress'ure,

some will takeit .-up,with sufficient rapidity in an openvessel; but generally the higher the pressure the more rapidly will the soaking be done. p The, process can be carried on in cold wa-' ter in the open-air, but will take longer, so

I prefer heat and pressure ,or item be first soaked in hot or' cold water in the openair,

. and then be subjectedto'heat and pressure, ac-

The wood, beingthus saturated with water in the openair or under pressure, is then passed press, compress, or condense? the fibers of the or vice versa, which drives out the moisture, and with it a portion of the intcrcellulose matter, which is transferred from in and around the fibers and held in suspension in 'fer should be heated above 200 Fahrenheit.

- When the fibers of the wood have been relieved from the pressure between thesurfaces they are comparatively dry and porous, and

sition. In thus expanding after the removal of. the pressure, the fibers beginto separate from each other and the intercellulose matter, their cohesion is destroyed by the pressure, and they are not so firmly held together, owing to an increase of the spaces between the fibers, caused by the displacement of all the particles, --the increased elasticity of the fibers, andthe and is now held in solution qr suspension by the water inwhich the wood is submerged, This intercellulose matter is thus gradually forced awayfrom its original position surrou'n ding'the fibers, 'and the cohesiveness of the fibers is thus destroyed.

When the fibers have been released from pressure they are again soaked, and the water rushes in to fill thepores of the wood as it ex- 'until the desired-disintegration and cleanliness of the fibersis obtained. The water also acts as a cushion, to pression of the fibers. g

This process of alternate pressure and expansion of the fibers has the effectpf separatmaking them elastic, tough, pliable, and soft, and retains them in theirf'ull natural length, and is kept up until most, if not all, of the in- The water which becomes charged with the between two or more surfaces, which squeeze,

7 wood in and upon the intercellulose matter,

the water, which water, for most woods, I pre- V prevent excessive comtercellulose matter is washed away from the fibers and is held in suspension in the water.

cording to the kind, of wood to be reduced.

expand retu-rning to nearly their-original p0 vabsence of some of /the intercellulose matter,

which was displaced by the first compression,

pands, and assists'in itsexpansion; and this v .w v y I j processof" soaking and crushing isrepeated- To greatly facilitate the soakip'g'where time" 40 is an object,l use a steam-ti'ght receptacle ing them into strings and separate fibers, and

which the greater part of the intercellulose' matter is first washed out before the fibers are subjected to an alkaline solution.

If the wood is poplar or any similar white wood, and contains no pitch, gum, rosin, or any resinous matter, the refining process can be carried on until the degree of desired fineness is reached, and this pulp can be subsequently made into paper-by the many wellknown manipulations.

When it is desired to make a very fine white paper, absolutely purcand free from all intercellulose matter, or which it is desired to make from woods (such as pine) which contain gums and resins, 1 allow the process, as above described, to continue until I have removed all the intercellulose which it is possibleto remove with hot water, when I draw 05, through suitable screens, all the water, replacing it with an alkaline solution. As the wood is now in such small fibers and comparatively free from intercellulose matter, the fibers are in the best possible condition to receive the alkaline solution to further reduce them, which solution maybe used in the open air or under pressure. I make it, preferably, of soda-ash rendered caustic by the addition of lime.

The process of alternate pressure and expansion of the fibers by passing them between two or more surfaces is continued, in connection with the alkaline solutionfin open air or under pressure, the same as is before done with water alone, and the solution may be hot or cold.

The advantage is, that this pressure and subsequent expansion process, when used while the fibers are comparatively clean and greatly disintegrated, in connection with the alkaline solution, result in a very speedy reduction of the fibers-to the purity required for;

the finest papers, and it is done with the expenditure of the least lime and smallest quantity of alkalies, as the alkalies are forced into the fibers by the crushers.

- ,Thealkaline liquor can now be drawn ofi' to be used again, or the soda can be recovered in any of the ways well known to the arts by evaporation and incineration. The pure fibers are then freed from all traces 'of -alkalies by washing in water, cold or hot, The pulp can now be emptied into the ordinary drainersto allow the-water to run away, and is ready for the subsequent manufacture into paper, and can, if desired, be bleached in the ordinary way when alone or combined with other fibers. If, however, it is desired to bleach the pulp before emptying it from the crushing-engine, the chlorine or other bleaching solution is added while it is still in the crushing-engine, and the washed pulp is again submitted to the vices, or

process of alternate compression and expansion, as already described, in connection with the chlorine-bath, which maybe done hot or cold, in the open air or under pressure. As by these means the chlorine is forced into the fibers in a very effective way, the process of bleaching is greatly shortened as to time and a materially-diminished quantity of chlorine is used. It is then emptied into the usual drainers, and may or may not, as is found desirable, be passed through an ordinary wet machine to remove the particles of wood. not thoroughly disintegrated. This completes the process of a reduction of the fibers to fine pulp. I t r There are many mechanical devices by which I can produce the effect of alternate pressure and expansion of the fiber, as described. For

instance, the wood can be passed between a.

stack of calender-rolls or two or more revolving rolls, whose surfaces may be smooth or corrugated and traveling at the same or different ratesiof speed. 1 can use a level plane, the surface of which may move or be stationary, which may be smoother corrugated, over whicha smooth or corrugated surface may travel, or a combination of these or similar dea machine similar to a putty-grinder, which is a deep circular pan, in which broad heavy wheels, rolls, followers, or chasers revolve on their faces and their own axes around a perpendicular driving-shaft, from which they obtain motionp These wheels or crushers rotate on this circular'plane (with sides) and press upon any material between them and the bed-plate. This makes pulp very rapidly, owing to the twisting motion of the crushers or wheels on the material to be disintegrated. Ihave also used a circular bed-plate, plain and corrugated, in which the chasers or rolls have plain or corrugated surfaces, or their combinations, which are coneshaped-i. 6., the chasers at the outer circum-' centraldriving-shaft the surfaces all travel at the same rate of speed. This plan, while taking more time, gives a long and tough fiber.

These and many other devices and mechanical combinations will accomplish my purpose, and I do not limit myself to them or any of their combinations.

A machine to work my process will .be the subject of a separate application for Letters Patent.

This process is veryeconomical in time, labor, machinery, plant, and chemicals, as the entire operation, from the crude fiber or wood to the refined and bleached pulp, fit for the finest grades of paper, can be carried on in one continuous operation and in one machine.

This present process difiers from Letters Patent No. 215,728, obtained by me May 27, 1879, in that while I there used water, alkaline solutions, and chlorine, hotor cold, in open air or under pressure, I now describe ,a

peculiar order in which they are to be used andthe particular state of the fibers at the time and expansion, as already described.

' packed.

each of the baths or solutions are to be applied to the material tobe pulped, in combination with the process of alternate pressure In order to operate the crushing-engine say one constructed upon the principle and after the style of a putty-grinder-so that the various operations described above can be carried on ,under pressure, the top of the machine can be inclosed with an air and steam tight cap or head, or the whole machine can be inclosed by an air and steam tight shell, the operating-shaft being passed through the shell, and the joint where it passes through being Man-holes and discharge-openin gs to put in the fiber and remove the pulp, respectively, and cooks and valves to pass in and take out the water and various solutions and steampipes to get up a pressure, can all be provided at such points of the apparatus as are sug-' gested by the attachments to an ordinary pressure pulp-digester and by the above description, or to the mind of any skilled mechanic or person skilled in the art of pulp-manufacture.

Having thus described my invention, what I claim as-new, and desire to secure by Let'- ters Patent, is-- I 1. The process of manufacturing paper-pulp from Wood or other vegetable fibrous material,

by soaking such material in water, then crushing, pressing, or squeezing it, then soaking it again, the operation of alternate crushing and squeezing to be continued until the desired cleanliness and disintegration of the clinging fibers are obtained, substantially as described.

2. In combination with the alternate compressing and expanding process described above, the process of washing with Water the fibers thus disintegrated,substantially as described.

3. In combination with the alternate .soaking, compressing, and expanding and washing- 4 5 out process, boiling the disintegrated fiber in an alkaline solution, whereby the fiber is converted into a finer pulp, substantially as described.

4. The process of alternately soaking and compressing or squeezing the material to separate the fibers, boiling the same in an alkaline solution, Washing out the latter, and then adding a chlorine or other bleaching s0- 1ution.,'substantially as and for the purposes wood or other. vegetable fibrous material into separate fibers, the further reduction'of the same by an alkaline disintegrating solution, substantially as described.

6. 'The process of soaking and crushing wood and other vegetable material in a chamber furnished with rollers to crush the said material, boiling the same in an alkaline solution, washing out the solution by means of water then treating the same with a bleaching solution, the whole operation being conducted in. the said chamber, whereby at any stage in the process the said rollers can be used to further crush the pulp or to force any of the liquor or solution into it, substantially as described.

7. In the process of reducing wood and other vegetable fibrous material to paper-pulp, crushing it in a chamber containing rollers, and then treatingit chemically in the same chamber to further reduce it, whereby the rollers used in the first stage to crush it can be utilized at any subsequent stage in the process to further reduce it, or to force the liquors used in the manipulation into and through the pulpy mass, substantially as described.

WILLIAM E. FARRELL.

Witnesses:

HENRY V. BUoKLEY, WM; H. CARSON. 

